Pump for elevating liquid



W. F. LESCHEN PUMP FOR ELEVATING LIQUID Filed Feb. 2 4, 1925 June 3, 1930.

'i Patented June 3, 1930 UNITED STATES WILLIAM F. IIESCHEN, OF ST. LOUIS, MISSOURI. I

PUMP FOR ELEVATIN G- LIQUID Application led February 24, 1925. Serial No. 11,144.

This invention relates generally to pumps for elevating liquids, and particularly to a pump for pumping liquid, especially oil, from below the ground.

As is well known, oil wells are usually quite deep, said wells frequently being thousands of feet in depth, and prior to this invent-ion the pumps used in oil wells usually each comprised a plunger arranged-to reciprocate in a cylinder, which plunger' was attached to the lower end of a rod or plurality of rods extending from above the ground. rIhe plunger reciprocated at a point relatively close to the bottom of the well, and because of this fact the rod to which said plunger was attached was of very great length. The purpose of the present invention is to produce a pump of the type mentioned which is so constructed and arranged that the length of the rod t0 which the reciprocating plunger is attached is greatly reduced, thereby reducing the initial cost of the rod and also reducing the power necessary to reciprocate said rod and the plunger because of the lessened weight f5 of said rod.

With the foregoing and other objects in view, the invention comprises the novel construction, combination and arrangement of parts hereinafter more specifically described S0 and illustrated in the accompanying drawings, wherein is shown the preferred embodiment of the invention. However, it is to be understood that the invention vcomprehends changes, variations and modifications which come within the scope of the claims hereunto appended. y f' Fig. I is a vertical section of the lower portion of my improved pump. f l

Fig. II is an enlarged fragmentary vertical section of the lower end of the pump illus- Atrated in Fig. I Y

Fig. III is a cross section on line III-III of Fig. II. p

In the drawing, A designates my improved pump, which comprises an outer ltubing 1 and an inner tubing 2. The outer tubing 1 has a reduced portion 3, said reduced Vortionl being connected to the lar er uppe ff portion of said tubing by means o a horizontal wall 4, The inner tubing 2 is of less'dameter than the outer tubing 1, so that an annular space 5 is provided between the walls of said outer tubing and said inner tubing. By referring to Figs. I and II it will be seen that the lower end of the inner tubing 2 is same in its proper position relative to the upper end of the opening 9. The plunger 7, as will be seen by referring to Fig. II, is provided with the usual packing rings 12 to insure Huid-tight contact between the periph eral face of said plunger and the wall of the inner tubing 2. The upper end ofthe sucker rod 8 is connected to a suitable mechanism which is located above the ground and which imparts reciprocating motion to said rod and to the plunger attached thereto.

Arranged at a point adjacent to the lower end of the pump A is a member 13. The member 13 is circular in cross section and comprises an enlarged head portion 14 and a reduced stem portion 15. As shown clearly in Figs. I and II, the head portion 14 of the member 13 is arranged within the inner tubing 2, and said head portion is adapted toreciprocate within said inner'tubing. To provide fluid-tight Contact between said head portion of the member 13 and the wall of the inner tubing, I employ packing rings 1G. The stem portion l5 of the member 13 extends downwardly from the head portion 14 thereof into the reduced portion 3 of the outer tubing 1, said stem portion 15 being of such diameter that it may be reciprocated within said reduced portion 3. To provide fluid-tight contact between the stem portion 15 and the inner face of the wall of the reduced portion 3 I employ packing rings 17. Extended through the member 13 is a central longitudinal opening 18, which is normally closed at its upper end by a ball valve I19, said ball valve being arranged within a cage 20 so that it will be retained in its proper position relative to the upper end of the opening 18.

The reduced portion 3 of the outer tubing is provided with a. comparatively thick botn tom wall 21 which has an opening 22 formed therethrough. Arranged at the upper end of the opening 22 and adapted to normally close said opening is a ball valve 23, there being a cage 24 provided to retain said ball valve in its* proper position relative to the upper end of said opening. ir'

Brior to placing my improved pump in operation, liquid, for instance oil, is poured into the annular space 5 between the tubings 1 and 2, this space 5, together with the space 6, being filled to the desired level, and also liquid is poured into the inner tubing 2. Assume now that the pump has been in operation and that the parts thereof are in the positions in which they are shown in Fig. I. rl`he plunger 7 is reciprocated by the mechanism above the ground, and on each upward stroke of said plunger a portion of that body of -oil which is located above the plunger will be discharged from the pump. It will be noted that on the upward stroke of the plunger the ball Valve 10 associated with said plunger is closed.

Confined between the plunger 7 and the upper end of the member 13 is a body of oil which is designated by the reference character X. Located in the spaces 5 and 6 and in the inner tubing 2 below the head -14 of the member 13 is a body of liquid already referred to, which will now be designated by the reference character Y. It will be noted that the body of liquid within the inner tubing 2 and above the member 13 rests upon the topA face 14a of the head 14 of said member 13, and it will also be noted that the body of liquid Y contacts with the lower face 14b of said head 14.

The height of the body of liquid Y in the space 5 may be approximately the same as the height of the entire body of liquid within the inner tubing 2 above the face 14a of the head 14. In other words, when the valve 10 associated with the plunger 7 is unseated and the liquid within the inner tubing above the head 14 is in the form of a continuous body which extends from the face 14a of said head 14 to the top of the pump, this body of liquid is approximately the same height as the body of liquid Y. The area of the face 14a of the head 14 is much greater than the area of the face 14b of said head, and the first thought would be that because of this greater area the total downward pressure of the liquid within the inner tubing acting on the member 13 would be greatly "in excess of the total `upward pressure of the liquid acting on said member 13. This, however, is not the case for the reason that there is a body of liquid Z in the reduced portion 3 of the outer tubing with which ythe face 14c at the lower end of the stem portion` 15 of the member 13 contacts,

' and while downward pressure is exerted against the wholeface 14a by the' body of liquid above said face 14a, upward pressure is exerted against the face 14C by the liquid Z below said face 14C. rllhe result of this is that in calculating the effective area of the face 14a the area of the face 14c must be subtracted from the total area of the face 14a, and when this is done it will be found that the effect-ive area of the face 14a is approximately the same as the area of the face 14". lt is apparent, therefore, that the pressure per square inch exerted by the entire body of liquid within the inner tubing 2 above the face 14a against said face 14a on the downward stroke is approximately the samer as the pressure per square inch 'exerted by the body of liquid Y against the face 14".

It has already been stated that on each upward stroke of the plunger 7 some of the liquid within the inner tubing 2 above the plunger 7 will be discharged from the pump. It is apparent that if some means were not provided to cause the body of liquid X to move with the plunger 7 'when said plunger moved upwardly, said plunger would move away from said body of liquid X, which at this time has been separated from the liquid vabove the plunger by the closing of the valve 10. In other words, the body o f liquid within the inner tubing 2 would be divided into an upper body, or that liquid which is above the plunger 7, and a lower-body, or that liquid which is below the plunger 7. It is plain, therefore, that when the plunger moves upwardly and the valve 10 closes a column of liquid X would be provided which is of much less height than the body of liquid Y, and consequentl the pressure per square inch of the body o liquid Y at the face 14b would be greatly in excess of the pressure per square /inch of the liquid X at the face 14a.

In View of the foregoing it is quite apparent that as the plunger 7 moves upwardly the pressure of the body of liquid Y would exert an upward force against the lower face 14b of the head 14, and because the pressure per square inch of the body of liquid Y at the face 14b multiplied by the area of said ,face 14b is greatly in excess of the pressure per square inch of the body of liquid X at the face 14a multiplied by the area of said face 14'a the member 13 would be elevated,V

and as the'valve 19 would be closed at this time it is plain that the body of liquid X would be lifted by said member 13. When the member 13 is elevated as described, it is plain that suction would be created in the reduced portion 3 of the outer tubing 1, which suction would have the elfect of unseating the ball valve 23 and drawing the liquid through the opening 22.`

The action of the pump oni` the upward `column of liquid which extends from the' face 14a of the member 13 to the top of the pump will be provided. As has already been stated, the height of this column ot liquid is approximately` the same as the height of the body of liquid Y, and because the faces 14e'bi and 14 have approximately the'.-

same effective areas there will be a balance of power, thedownward pressure exerted against the face 14a beingapproximately the same as the upward pressure exerted against the face 14". However, the member 13 is of considerable length and Consequently of.

' some weight', and because the pressure all around said member 13I will be approximately equal said member will move downwardly by gravity, and this downward movement of the member A13, added to the dowm ward pressure of the body of liquidl within the tubing 2 above the member 13, will be.`

, which was below the member 13 to be added to the body of liquid X above said member.

y tIt is` plain, therefore, that a reciprocatby the plunger of the pump by an auxiliary body of liquidasaid separated bodies of liquid being reunited to provide suiiicient force to return said auxiliary body of liquid to its normal position after it has perforniedits functionv of raising one of said bodies of liquid. v

To provideA for' the escape of gas which may accumulate within the reduced portion 3 below theface'llc of the member 13,1 form an elongated opening 27 adjacent to the lower end of the stem portion of saidmember13. l

This opening is so arranged that at the upper endof each stroke of the member 13 a portion of said elongated opening will be `above the horizontal wall. Ltand a portion thereof below said horizontal wall. In this way communication is obtained between the interior of the reduced portion 3` and the space 6v which will permit any gas' which may be within said reduced portion to pass into said space 6 and bubble upwardly through the liquid in the space 5 and escapeat thc top of the pump.

While I have stated in this specification that the height of the column of liquid withinthe inner tubin 2 and the'height of the column of liquid t* are approximately the same, I did this to simplify the` description of the invention.v However, I desire it to be understood that it is not necessary that 'said columns of liquid be the same height, but

their heights and pressures may vary without interfering with the successful operation of the invention.

I claim:

1. -A pump for raising fluids from great depths, comprising an outer casing adapted l to extend from the level of the liquid upwardly to a point substantially adjacentl to t-he outlet of the well, an inner casing arranged in concentric relation with respect to the` outer casing having its lower end terminating above the extremity of the outer casing, and a plurality of independently arranged plungers located within the innereasing, said plungers being so constructed and arranged that. movement imparted to one of the plungers to drawupwardly liquid located above the plunger will result in upward move- ,ment being imparted to the lower plunger by means of liquid in the outer casing working on the under face of the lower plunger. 2. A pump for elevating liquids from great depths, comprising an outer casing arranged to extend from the ground level to the fluid level of the well, an inner casing located substantially concentric with respect to the .outer casingand arranged to extend downy wardly and to terminate above the lowerextremity of the 'outer casing, means "closing the lower extremity of the'outer 'casi iig,'sa id means comprising a plunger adapted to move within the inner casing, and a second plunger mounted in the inner casing 'and separated' from and-independent'of the first plunger",

lthe plungers being so constructed and arranged that movement imparted to the upper plunger when the pump is lull of liquid're- In testimony that I claim the foregoing I hereunto aiiix my signature.

WILLIAM r. LEscHEN. 

